Saying Vayechulu Makes a Person a Partner in Creation

Another interpretation: the works were completed and they kept stretching forth and continuing. "And all their host": there are three hosts. There is a host for the heavens and the earth, as it is written, "And the heavens and the earth were finished and all their host" (Genesis 2:1). There is a host for disciples, "All the days of my host I will wait" (Job 14:14). There is a host for sufferings, "Is there not a host for man upon earth?" (Job 7:1). Rav said, and some say Rabbi Yochanan: Even an individual who prays on the eve of Sabbath must say "vayechulu," for Rav Hamnuna said: Whoever prays on the eve of Sabbath and says "vayechulu," Scripture credits it to him as though he became a partner with the Holy One, blessed be He, in the work of creation. Do not read "vayechulu" [they were finished] but "vaychallu" [they finished]. Whoever prays on the eve of Sabbath and says "vayechulu," the two ministering angels who accompany a person place their hands upon his head and say to him, "Your iniquity is removed and your sin is atoned" (Isaiah 6:7).